Transmitter



July 14, 1925.

R. R. HERRMANN TRANSMITTER Filed Jan. 24, 1922 ||.III/ 1 I IIII k III Patented July 14, 1925.

1,545,828 UNITED STATES PATENT OFFICE.

RAYMOND R. HER-RMANN, OF ST. PAUL, MINNESOTA, ASSIGNOR T "WESTERN ELEG- TRIG COMPANY, INCORPORATED, OF NEW .YORK, N. YQA CORPORATION OF NEW YORK; V

TRANSMITTER.

Application filed January 24, 1922., Serial No. 531,323.

To all whom it may concern.

Be it known that I, RAYMoND It. I'IERR- MANN, avcitizen of United States, residing at St. Paul, in the county of Ramsey, State of Minnesota, have invented certain new and useful Improvements in Transmitters, of which the following is a full, clear, concise, and exact description.

This invention relates to transmitters and particularly to a telephone transmitter of the multicellular type.

In various transmission systems there eK- ists a demand for a high resistance and high power transmitting device which will satisfactorily convert sound Waves into corresponding electrical vibrations. It is also often required that such a device shall op erate satisfactorily on comparatively high potentials and shall not, under such conditions, be subject to severe burning or packmg.

It is an object of the invention to provide a multi-cellular transmitter which may be of high resistance and in which the potential drop is distributed approximately uniformly over the different cells.

Another object is to provide a transmitter which will be cheap to manufacture and which will not be subject to severe packing or burning of the granular material.

There is provided a multi-cellular transmitter having conducting diaphragms as partitions between the various chambers, these diaphragms being separated from each other by means of elastic rings.

Referring to the drawing, there is disclosed a transmitter button embodying the features of this invention, the button being shown assembled in the well known type of centrally damped transmitter. The transmitter button comprises a metallic housing in which are assembled the back electrode 6 and the diaphragms 7, 8 and 9. The diaphragm 9 which also serves as a front electrode is secured to a button 10 by means of a mica annulus 11, the button being secured at its periphery to the housing 6 by means of a clamping ring 12. The diaphragm 7 is separated from the back electrode 6 by means of a ring 13 of felt, soft rubber or other elastic and insulating material and is separated from the diaphragm 8 by means of a similar ring 14 of felt or similar material. A felt ring 15 likewise separates the diaphragm 8 from the electrode or dia phragm 9. The ring 13 is so dimensioned asto be more elastic than the ring 1% which in turn. 1s more elastic than the ring 15.

The shank 16 of the transmitterbutton is secured to a bushing 17 in a bridge 18. The bridge is in turn secured to the transmitter face plate 19 by means of screws 2020. The face plate is provided with a mouthpiece 21, and a standard transmitter back 22. A diaphragm 23 is held in. position as shown by means of a centrally damping spring 2 1 which bears against the button 10.

Inassembling the transmitter button, the various chambers are partially filled with the front chamber and exerting pressure upon the diaphragm 8 which in. turn moves to the left compressing the carbon in the metal chamber and exerting pressure on the diaphragm 7 which likewise moves to the left and compresses the carbon in the back chamber. Preferably, the rings 13, 14: and

15 are so proportioned that the diaphragm 8 moves through a distance twice as great as the diaphragmfl, and diaphragm 9 moves through three times as great a distance as diaphragm 7 As a result the compression of the carbon in the various chambers is approximately equal, and the total voltage drop through the transmitter button is distributed approximately uniform through the various chambers. Consequently, the trouble due to burning of the carbon is reduced as is also the liability to packing of the carbon and resulting low efficiency. The arrangement disclosed'makes it pos sible to provide a transmitter button of high resistance in which the agitation of the carbon granules is practically constant throughout the construction.

What is claimed is:

1. A current varying device comprising a housing, a' plurality of conducting diaphragms separating said housing into a plurality of chambers,-comminuted resistance material in said chambers, and elastic means for coupling said diaphragms.

2. A current varying device comprisinga housing, a plurality of conducting diaphragms separating said housing into a plurality of chambers, comminuted TGSlStElIlCB material in said chambers, a vibrating mem- V Vber and elastic rings coupling said diaphragms at their peripheries whereby the vibrations of said member are transmitted successively to said diaphragms;

3. A current varying device comprising a housing, a plurality of conducting diaphragms separating said housing into a plurality of chambers, comminuted resistance material in said chambers, and elastic members having different degrees of elasticity coupling the diaphragms at their peripheries. I

i. A current varying device comprising a housing, a pair of carbon diaphragms spaced therein, a fixed electrode, a movable electrode, said electrodes being exterior of said diaphragms, comminuted resistance material in the chambers between said diaphragms and electrodes, and elastic ring members positioning said diaphragms with respect to the electrodes and each other, said ring memapproximately uniform to the diaphragms and the fixed electrode.

5. A current varying device, comprising a housing a pair of carbon diaphragms spaced therein, a fixed electrode, a movable electrode, said electrodes being exterior of said diaphragms, comminuted resistance material in the chambers between said diaphragms and electrodes, and elastic ring members positioning said diaphragms with respect to the electrodes and each other, said ring me1nbers having such elasticity that the movable electrode upon an applied force is displaced approximately three times as far as the rear diaphragm, and the front diaphragm is displaced approximately twice as far as the rear diaphragm. V

In witness whereof, I hereunto subscribe my name this twentiethday of January, A. D. 1922,

RAYMOND R. HERRM'ANN. 

